Principle, Principle 2 – Bio-Rad Human MMP and TIMP Assays User Manual
Page 4
Principle
Technology
The Bio-Plex
®
suspension array system is built upon the three core
elements of xMAP technology:
n
Fluorescently dyed microspheres (also called beads), each with a distinct
color code or spectral address to permit discrimination of individual tests
within a multiplex suspension. This allows simultaneous detection of more
than 100 different types of molecules in a single well of a 96-well microplate
n
A dedicated flow cytometer with two lasers and associated optics to
measure the different molecules bound to the surface of the beads. In
the Bio-Plex
®
MAGPIX
™
system, the sample is injected into a chamber
where the beads are imaged using LED and CCD technology
n
A high-speed digital signal processor that efficiently manages the
fluorescence data
Assay Format
Bio-Plex Pro
™
assays are essentially immunoassays formatted on
magnetic beads. The assay principle is similar to that of a sandwich
ELISA (Figure 1). Capture antibodies directed against the desired
biomarker are covalently coupled to the beads. Coupled beads react with
the sample containing the biomarker of interest. After a series of washes
to remove unbound protein, a biotinylated detection antibody is added
to create a sandwich complex. The final detection complex is formed
with the addition of streptavidin-phycoerythrin (streptavidin-PE or SA-PE)
conjugate. Phycoerythrin serves as a fluorescent indicator, or reporter.
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